Many industrial processes generate wastewater streams that contain small mounts of environmentally hazardous contaminants. Examples of such industrial processes include electroplating, circuit board manufacturing, photographic processing, and metal finishing. The wastewater generated from such processes must be treated as hazardous waste.
From an environmental standpoint, the hazard arises not from the water itself, but from the materials contained within the water. Examples of such materials include metals, such as copper, silver, nickel and lead; salts of these metals; and oils. Even though the water itself is not an environmental hazard, it adds to the problem the plant operator faces in disposing of the wastewater. Typically, waste removal fees are based on both the environmental hazard posed by the product, and of the volume of product. The difficulty in dealing with wastewater products is that the water, while not hazardous, creates a large volume of material that must be disposed of. Because of the bulk and the liquidity of the water, the cost of removing, landfilling or treating the wastewater produced by the industrial operation is quite expensive.
Therefore, the removal of the water component from the wastewater stream, while retaining the hazardous material residue could likely result in substantial savings to the waste generator. With the water removed, the contaminant residue is sufficiently small so as to be relatively inexpensive to dispose of, even in a special or hazardous material landfill.
To this end, several methods have been devised for separating the water component of a wastewater stream from the hazardous material residue component. Many plants, especially those producing large volumes of contaminated wastewater, have on-site treatment facilities that separate the contaminant residue portion of the wastewater. Unfortunately, although in-plant facilities work well in large scale operations that produce large mounts of wastewater, they are often not cost effective when used in operations that generate only relatively small amounts of wastewater (e.g. from 500 gallons per week to several thousands gallons per week). Smaller generators generally cannot justify the cost of building their own treatment facility, and also do not want the problems that accompany a treatment facility. For example, one of these problems is that an in-house treatment plant must be operated by a certified operator. Additionally, the typical cost for setting up an in-house treatment facility is 20,000 to 25,000, and is often much more expensive.
Therefore, it is one object of the present invention to provide a means for treating wastewater to remove the water component of the wastewater, that is adaptable, and affordable for use by generators of relatively small amounts of wastewater.